December 2019 United States airstrikes in Iraq and Syria

The December 2019 United States air strikes in Iraq and Syria occurred on 29 December 2019 when the United States carried out five airstrikes against Kata'ib Hezbollah targets in Syria and Iraq in retribution for their killing of a US civilian contractor in a rocket attack on the K-1 Air Base in Kirkuk two days earlier.

Background
In the aftermath of the Iraqi Civil War's conclusion in 2017, the Shi'ite Popular Mobilization Forces - once a US ally in the fight against the Islamic State - became opponents of continued Western interference in Iraqi affairs. The PMF was backed by the Iranian government, and, with the start of the 2019 Persian Gulf crisis, Iran began directing its Shi'ite militia allies in Iraq and Yemen to act against the US and its allies; on 14 September 2019, a Shi'ite militia's drone attacked Saudi oil facilities at Abqaiq-Khurais and disrupted ARAMCO's oil exports. A day later, the USA and Iran nearly went to war, with the USA warning Iran that it was "locked and loaded" and waiting for Saudi Arabia's signal to attack. Ultimately, the tensions calmed, but the US and Iran remained wary of the other's actions. Over the next few months, Iran's Quds Force supplied Iraqi Shi'ite militias with weapons with which they could attack US and Iraqi security forces in Iraq.

On 27 December 2019, the Iraqi Shi'ite Kata'ib Hezbollah militant group fired 30 rockets at the K-1 Air Base in Kirkuk, Iraq, targeting US servicemen participating in Operation Inherent Resolve. A US contractor was killed, while 4 US servicemen and 2 Iraqi security personnel were wounded. President Donald Trump was told that Kata'ib Hezbollah was behind the attack, and he decided to order retaliatory airstrikes to deter future attacks.

Airstrikes
At 10:30 AM on 29 December 2019, US Defense Secretary Mark Esper informed Prime Minister of Iraq Adil Abdul-Mahdi of the US plans to launch airstrikes on Kata'ib Hezbollah, which Abdul-Mahdi strongly objected to and condemned. At 11:00, F-15 fighter jets attacke three Kata'ib Hezbollah locations in Iraq and two in Syria, including weapons storage facilities and command and control locations. Four militia leaders were killed, while several ammunition caches were also destroyed, causing secondary explosions. Over 25 militants were killed and 55 wounded, and Kata'ib Hezbollah vowed revenge for the attacks, while Iraq, Iran, and Hezbollah condemned the attacks; Bahrain and Israel supported them.